creating a simple digital logic circuit simulator

Hi,

Im in the process of writing a simple digital logic circuit simulator
application (similar to B2Logic). What would be the best approach or
design for a project like that? I mean should I use the object-oriented
design: making gates as classes, and if so, should I make ALL gates as
classes or should it be just the BASIC gates (AND, NOT, OR) and build
all other components (XOR, NOR, NAND, FULLADDER, etc.) as C-style
FUNCTIONS that use those basic classes?

I guess my questions should be: Whats the most common design in
commercial applications (e.g. B2Logic)? Is it pure, C-Style code, or is
it OOD? And how is it generally done (details are highly
appreciated)???

Thank you.

Pete

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